Apollo 17 LM Pilot and professional geologist Jack Schmitt examines a boulder at the Taurus-Littrow landing site, December, 1972
During my recent appearance on The Space Show, a caller questioned the need for people on the Moon. If teleoperated robots can be used to mine resources, manufacture useful products, and set up a lunar outpost, as I have proposed, why do we even need people on the Moon? The caller’s question touches once again on the age-old argument about the transport and support of humans in outer-space, where their presence is both mass- and power-intensive and thus, more costly. But we shortchange humanity if we fall into the trap of believing that a human presence on the Moon (or in space in general) is either not necessary or that it is only required for making repairs, or for updating equipment.
Now that returning to the Moon is in the news, “Why send humans into space at all?” will be asked, again, as it lies at the heart of a very old debate and battle about space. It is the same question that spawned the 2014 Congressionally mandated study by the National Academy of Sciences. That effort posed two “enduring questions”: How far can humans go and what can they accomplish when they get there? But how can anyone truly know the answers to those questions or make sweeping pronouncements about them? Fortunately, because we’ve had 50 years of human space missions, we have demonstrable evidence about the “usefulness” and promise of humans living and working in space.
In December, we’ll celebrate the 45th anniversary of the Apollo 17 mission of 1972 – the first (and so far, only) mission to fly a professional geologist to the Moon – Lunar Module Pilot Jack Schmitt. The Apollo 17 landing site was a complex, multiple objectives site whose complete and thorough understanding and characterization was not likely within the allotted 3-days there. Nonetheless, Apollo 17 crewmembers Commander Gene Cernan and Jack Schmitt traversed and explored the Taurus-Littrow valley “from one end to the other” (as Gene would say from the Moon), and where they made several significant discoveries. They found highland rocks of extreme antiquity, almost as old as the Moon itself (4.6 billion years). They sampled large boulders that represented the remnants of ancient collisions that created the large, circular mare basins more than 3.9 billion years ago. They discovered orange and black soil at Shorty crater, which later was found to be composed of tiny beads of glass created when lava generated 100s of km deep within the lunar interior erupted and sprayed into space and fell back to the surface. And they collected pieces of material thrown out from one of the youngest large craters on the Moon, Tycho, more than 2200 km distant and whose impact occurred “only” 100 million years ago. Eight hundred and forty pounds of lunar rock and soil samples were returned to Earth by American astronauts over six lunar missions. These samples have given a tangible, invaluable context to scientists studying the Moon remotely, for over 48 years.
Could autonomous machines or those under remote control have carried out this complete and thorough exploration of a complex geologic landing site? Most scientists involved in the Apollo program would argue that machines could not have accomplished what the Apollo 17 crew managed to do. Certainly, scientists studying Mars via rovers have often wished that a thinking, walking and talking human could replace that machine. Productive geological fieldwork requires more than the ability to make measurements and pick up rocks – it is important to sample the right rocks, but also to put visual and mental data into a conceptual framework that guides the geologist toward reconstructing the history and processes of a planet. Of course, “grab samples” can be informative when the site is geologically simple and the rocks have a clear context. An example of this might be collecting samples from the youngest lava flow on the Moon. A scoop of fresh regolith from such a site would most certainly contain chips of lava from that flow, allowing for the determination of its composition, age and the nature of its source region. But complex areas, where comprehensive studies demand a real time, in-depth, working knowledge of complicated geologic “mixes,” require humans who can recognize and mentally process what they see before them.
Fieldwork is a complex discipline, whereby an experienced geologist maps an area and chooses samples – not just rocks picked up at random, but rather carefully chosen – significant and representative samples that inform us about process and history. In any natural setting, literally billions of bits of data could be collected. And that’s what a machine does – it collects data. A human field scientist also collects data, but they also are able to high-grade it by collecting only the most significant and relevant data. It takes extensive study, then training and experience in the field, to be able to recognize the significant and distinguish it from the trivial – to see the big picture. We often remark on the Mars Exploration Rovers for their accomplishments, yet for all the data collected, we still cannot draw a simple geologic cross-section of those landing sites, and we still do not know the origin of many of the rocks at the site (igneous or sedimentary). A human geologist would have obtained this important information after a few hours of fieldwork. The mass- and power-intensive humans give a big return on their investment.
In addition to fieldwork, humans possess other qualities that machines do not. The ability of people to recognize, diagnose and solve equipment malfunctions has been proven time and again throughout the history of the space program. The Apollo 17 crew not only explored the valley of Taurus-Littrow, they also deployed an experiment package that required careful installation and alignment. They fabricated and replaced the fender of their lunar rover by using the famous stand-by of all terrestrial repairmen, duct tape and plastic maps (if the rover fender had not been replaced, the dust kicked up by the rover wheels would have soon coated all electronic equipment, leading to overheating and termination of the surface exploration). During the Skylab program (1973), repair work by the crew saved the crippled space station after it was damaged during launch. Literally heroic efforts by Pete Conrad and his crewmates Paul Weitz and Joe Kerwin allowed not only habitation of the overheated Skylab, which was then used by two subsequent crews, but literally saved the entire program. When it was discovered after launch that the mirror of the Hubble Telescope had been ground incorrectly, the crew of Shuttle Mission STS-61 were sent on a mission to put corrective lens on the telescope, again saving the entire program. The assembly and numerous repairs and maintenance of the International Space Station (ISS) require the use of both human and robotic assets to complete, without which the program certainly would not have survived. And this new era in space spawned an explosion of engineers and scientists, and dominated our culture with space movies, architecture, fashion and technology.
Fortunately for humanity, people are required in space to do what only people can do (while also dreaming up new things to do and new ways to do them) – tasks requiring experience and knowledge guided by reasoned judgment and imagination. The ability to act and then learn from such action is critical. People will always innovate solutions for seemingly intractable problems that may arise. A combination of fine-scale manual dexterity and expert, informed knowledge and the ability to react, creates an ease of capabilities in space unachievable by machines alone. The template created during the assembly of the ISS – in which people using robotic machines assembled a complex spacecraft in orbit – is the most likely and productive path for future space activity of all kinds.
Do we need people on the Moon? Fortunately, the answer is a resounding “Yes!” Humans bring unique capabilities that are needed to accomplish new things – unknowable things, things that will enhance our lives on Earth. Studies that conclude that only robots should conduct space and surface operations – as people require protective equipment and habitats – is shortsighted and harmful to a vibrant, intelligent, and inquisitive society. Both humans, and the machines they create to assist them, are required for success in this grand adventure.
The primary reason, IMO, for sending people to the Moon (ASAP) is to see if our species can live and reproduce on a low gravity world without significant deleterious effects to our health and reproduction.
If it turns out that low gravity is harmful to human health then we need to find out how difficult or easy it is to mitigate or to eliminate such health effects, possibly through exercise, temporary periods of hypergravity, or by simply wearing weight vests.
Economically, I think its pretty obvious that the Moon is going to be the primary destination for space tourism during the rest of the 21st century. Propellant producing water depots should make such commercial lunar journeys affordable for at least 50,000 of the wealthiest people on the planet. Space lotto winners could add even more traffic to the Moon.
Just 500 people traveling to the Moon every year could drive cost down to a level that could eventually make it affordable for every millionaire on the planet to travel to the Moon. There are nearly 15 million millionaires currently on Earth.
Marcel
“If it turns out that low gravity is harmful to human health-”
Marcel, we keep revisiting this low gravity issue over and over again, somewhat like the “man vs robots in space debate” detailed by Dr. Spudis.
Except there is no debate on low gravity- it is harmful.
You might think it is obvious that space tourism is going to be affordable but again, considering the commercial space station situation, there is no debate.
NASA cannot give the ISS away to private concerns because there is no legion of thrill-seeking millionaires clamoring to expend their fortunes on vomiting in microgravity and looking out a window. Space tourism is a dead end.
Humans expanding into the solar system is about the survival imperative: insurance against extinction. Which, whether the DOD wants to admit it or not, is their responsibility.
Along with comet and asteroid deflection.
Gerard K. O’Neill charted the course to take in space in the 70’s and his conclusions are still valid. His work eliminated low gravity environments early on as contrary to a million years of evolution. Humans require certain conditions, such as Earth gravity and radiation, to thrive. These basic requirements cannot be waived because it is more convenient to live on Mars or the Moon.
Artificial moons (Bernal spheres) are the inconvenient necessity.
There’s plenty of evidence that microgravity is harmful to human health.
But there is no evidence that lunar gravity was harmful to the Apollo astronauts. Apollo astronauts never resided long enough on the lunar surface in order for NASA to find out. So we simply don’t know if living under a lunar gravity is harmful or harmless. But we definitely need to know such things!
So a permanent lunar outpost could quickly tell us a lot about how well humans can adjust to low gravity environments.
However, I do agree with you that in the long run, most humans living beyond the Earth in the rest of the solar system will probably live in rotating artificial gravity producing habitats.
Marcel
I have always been more of an advocate for Robbie the Astronaut over Robbie the robot. There is no replacement for actually experiencing the exploration of any facet of land sea or air.
Well…we have a Moon rocket to take humans back almost built. Except the 4 billion dollar a year money hole going around in circles in LEO means only a few launches a year are planned. That is the first problem- we need to abandon LEO and Mars as the dead ends they are. A lunar return will require a new shuttle era launch schedule of 6 to 8 launches per year. Since the shuttle costs to reuse the RS-25 and SRB’s (not to mention the orbiter) never broke even it will cost the same.
And we need a lander. The Blue Moon looks good but maintaining the hydrogen propellant for the three day trip and however long it stays on the surface is the second problem. As far as I know there is no actual functioning cryo-cooler hardware being built and tested right now. Methane would be easier to store and maintain and hydrogen turbopumps have been converted to push methane so that might move it along. For any sustained program of commutes between Earth and the Moon a water shielded lunar cycler is also going to be required. Otherwise the career radiation dose will accrue too fast, especially for young females.
The shielded cycler brings up the question of where humans are going to live. A wet workshop can be partially filled with a water shield and connected to an equal mass with a tether system to provide gravity and this would eliminate dosing and debilitation. The lunar village concept of simply scraping and piling up regolith over a habitat has some merit for surface habitats. So if astronauts are going to go to the Moon for a 3 or 4 year tour in my view they will be periodically going back up to Low Lunar Orbit (LLO) to a 1G space station for rehabilitation. For surface excursions I see them traveling in a “water truck” with a hundred plus ton water shield around them.
The third problem, as always, is some reason to commit to a permanent human cislunar presence. I have commented many times on the various venues that justify a permanent lunar return. GEO human-crewed telecom platforms shielded with lunar water, DOD spaceships carrying the strategic nuclear deterrent in deep space, and space solar energy are in my view all good reasons to double the NASA HSF budget. The ice and likely giant lava tubes to build factories in are waiting.
Sure, its fine to send a geologist to the lunar surface. But it is expensive. The astronaut has to survive. The robot is expendable.
The geologist on the lunar surface always has the window of his suit between him and the lunar surface. He has no senses other than vision (no smell, taste, touch) and the visor can be smudged/dirty/dusty/fogged/wet/moist on the inside or outside, filtering/reflecting/refracting light in who knows what way. His vision is likely a mere trichromatic perception (some few can see tetrachromatically). But in either case, the receptors are limited. Robotic assets on the lunar surface can have the full range of senses, whatever is deemed necessary and augmented as time goes on. Hearing? Seismic detectors. Smell and taste? Chemical analyzers. Touch? Special sensor surfaces on robotic fingers. But add to that spectral analyzers, lasers, ranging scanners, magnetic/electrical property detection and any other property scientists could want to measure could have sensors. Does a human need to wield the sensor or robot? Both can, of course, but cost (money and safety) is a concern.
Also, he brought up on the show a concern about the bandwidth needed to send all the robotic sensor data to the hall of assembled geologists and other experts on the Earth surface so that they can provide their collective guidance, insights and wisdom rather than relying upon one sole geologist. Laser communications would open that bottleneck and they are working on it.
The lunar surface geologist is lugging a heavy and unlimber suit around. It is hard to move and bend over and pickup a rock. It seems to be a distraction to be enclosed thusly, experiencing the risk of falling down. or having to sprint for a hideout from radiation blasts when the call is put out to do so.
He is right about humans on the surface (or in orbit) being able to handle unpredictable or unplanned situations (as well as reduce latency with robotic control). But the extensive usage of robotic assets seems intuitively logical. Mass produce them to get the cost down. Lose some and who cares? Lose a human and it is bad. So, humans ARE valuable for unplanned situations that involve survival and mission success. With robots that are cheap enough, they are expendable.
Sure, its fine to send a geologist to the lunar surface. But it is expensive. The astronaut has to survive. The robot is expendable.
At the levels of money being spent for modern robotic missions such as MSL or JWST, that is becoming a debatable assertion.
Does a human need to wield the sensor or robot? Both can, of course, but cost (money and safety) is a concern.
It’s not a simple cost/safety calculus — scientific return must also be considered. The points and examples that I make in my piece are that human field exploration is both more efficient and more thorough than robotic missions (and some cases, discoveries have been uniquely enabled by the presence of people).
The lunar surface geologist is lugging a heavy and unlimber suit around.
This is indeed a problem and must be addressed for future human missions. Several technical solutions have already been proposed to alleviate the limitations of existing pressure suits.
But the extensive usage of robotic assets seems intuitively logical
And nobody is advocating against them — the argument is that robotic assets alone are inadequate, not that they are undesirable.
I guess there is a difference here is estimating the cost and capabilities of robotics. I agree with you for the near term, robotics can be expensive. But given the accelerating pace of robotic technology (e.g. automated driving), it seems that rather than the cost going down, it should get less.
The problem with space robots is that they are almost always one-offs. They HAVE to work since they are mission critical. Don’t make them mission critical. For Earth geological fieldwork, there has been little push for robots given the extensive availability of grad students. But even so, the usefulness of drones (more expendable than grad students) in geological fieldwork is clear. So, given the training of a rover to look for interesting or anomalous things (rather than looking for children or pets running in front of it in the self-driving car application), the robot can continuously look for things that might interest scientists and be of practical use to humanity.
I always have trouble about the concept of “scientific return”. Someone, likely a group of scientists, think some sort of science is useful (via the Decadal Survey or some workshop) and that the public should trust them. I think the risk of gathering most science is not worth a human life. I have heard of examples of testing of drugs being examples where it might be worth the risk. Looking at rocks? Hard to see how it might be considered justified.
It is a nice luxury to have humans on the surface and we all should be pushing for this, but it seems possible to have them all remotely, safely located and let the robots gather data and take the risks.
I think the risk of gathering most science is not worth a human life
Nobody is forcing anyone to go and do field work on the Moon. Your judgments about the value of it may not correspond to those of others. You are fundamentally arguing against a human space program – period. Fine, but most in the space field do not look at it that way.
It is not a matter of force. It is a matter of moral and ethical perception. Does a society allow or enable someone to do something that is unnecessarily risky? Especially since that society is paying for it? I recall being involved in lunar surface suit design and it is very complicated requiring alot of redundancy and backups. That makes the suit heavier. We had to design sorties to handle solar radiation events (enough time to get to shielding). Even a human driving a rover cannot be at high speed since it is offroad driving and accidents with humans need to be balanced by need (i.e. risks balanced by the need for a emergency return due to crew medical issues). So, perhaps enough engineering can be done to make it relatively easy and safe to do lunar surface work. I am not aware of this state existing at this time or in the near future. I am simply saying is looking for rocks a good use of risk.
Recall that John Kennedy only wanted to send a man to the Moon and bring him back safely. It was not to do science. It would have been ludicrous for Kennedy to have said he wanted to send man to the Moon to do science and bring him back safely. So, as we know, it was a race with the Soviet Union to prove which society was better. They did science on the lunar surface but that was a side effect.
When the first Shuttle was lost, they realized it was absurd to risk lives for something that could be done robotically. Before that, all payloads were to be launched with the Shuttle. I was surprised to see that goal! In retrospect it seemed foolish, but they felt it was extremely safe and wanted to have a high launch rate. We see how that worked out.
It is a philosophical question of course. Back in the day, life was cheap (which means humans were expendable). Losing large fractions of a ship’s crew (or expeditionary force) in scientific or exploratory voyages was acceptable. They did not have the option to do otherwise (i.e. use robots). We could go back to that notion and simply shrug at similar losses in space since no one is forcing them to go into space. I doubt it unless there is a good reason since we have increasingly powerful robotic assets to do the work.
There are good reasons for humans to go into space. Reduce latency is the primary one. A surface or orbiting base on the Moon and a orbiting base for Mars make a lot of sense for humans to populate. Sure it is more risky than sitting at home, but engineering can be used to make it safer.
I am simply saying is looking for rocks a good use of risk.
Actually, I think that you mean to say exactly the reverse of that. But mis-statements aside, you still have not grasped my central point — field scientists do not simply “look for rocks”. They attempt to reconstruct process and history through an iterative loop of observation, sampling, re-examination, and constant revision of an evolving conceptual framework. Field science is something that people do; while robots can be useful assistants (although to date, that experience has been mixed), they cannot replace the productivity and perceptional acumen of the human observer in the field.
” I recall being involved in lunar surface suit design and it is very complicated requiring alot of redundancy and backups. That makes the suit heavier. ”
Since you are willing to allow for great advances in robotics to make more elaborate missions cheaper (“I guess there is a difference here is estimating the cost and capabilities of robotics. I agree with you for the near term, robotics can be expensive. But given the accelerating pace of robotic technology ….”) you should allow for some advances elsewhere.
As only one example, development of a cryogenic PLSS would allow reduction in cost, complexity and weight and is an increasingly well understood technology.
One of the great advantages of having a permanently occupied lunar outpost is that robots can be utilized and maintained by astronauts for the continuous exploration of practically every region on the lunar surface.
And that would include the robotic retrieval of rocks and regolith from practically every region on the Moon for eventual return to Earth, stowed aboard vessels returning astronauts to Earth after their multi-month or multi-year stays on the lunar surface.
Marcel
Keeping the bobcats going to continually expand a lunar village would require constant maintenance. Whatever system is used it will almost certainly require scraping and piling up several feet of regolith over the habitat as rad shielding. Explosives might be useful.
No idea how large a Moon base would be after ten years or so because that would depend on just how many new habitats are constructed per month. Each habitat might be more like a greenhouse than anything else with plants everywhere to provide food and supplement life support. No lava tubes in the vicinity of the ice mean water trucks could be used if distant tubes were found and utilized and as I have commented in the past these water carriers could be used as radiation shielded surface exploration vehicles.
There is the old PACER concept also:
https://en.wikipedia.org/wiki/Project_PACER
Until the Geologist brings samples into the lab/habitat and start running tests.
Yes, we should go. There have always been places to go which were inhospitable, and the Moon is even more extreme, but not different in kind. Many times we’ve had to step up, using intellect and technology to overcome those challenges. This really isn’t so different.
I see we’ve done a lot and made great progress in 50-some years. But to review that many years of missions, and realize we don’t have a single data point, not one measurement, to help us decide an appropriate, livable gravity prescription–well, hindsight is 20-20, but wasn’t there some mission that was not as important as the gravity Rx?
Let’s go to the Moon, and bring our robots with us!
“-we don’t have a single data point, not one measurement, to help us decide an appropriate, livable gravity prescription-”
Sure we do, it is called 1G. Earth gravity is the “prescription” and the Gemini 11 mission in 1966 shows the most practical technique to effect artificial gravity: the tether.
Gemini also showed how long it takes to start debilitating in microgravity: 11 days.
If you want a data point use that and apply that 16 % Earth gravity to 11 days and call it 20 days till debilitation begins on the Moon after descending from a 1G- LLO space station.
Are astronauts going to have to go back up to LLO after 20 days on the Moon? Probably not. A wild guess would be 2 months “down” and then at least 1 month “up” but depending on what kind of rotation they use it might be equal time spent in LLO and on the surface.
With 2 months up and 2 months down an astronaut would take 6 trips a year and over a 4 year tour 12 trips down and 12 trips up. All just speculation though.
Hey Gary,
OK, I was talking in a kind of shorthand, and should have been more clear. So, my position is yes, we have plenty of data, a “control group” if you will, for our experiment in the form of 1.0 G, normal life on Earth.
We also have plenty of evidence that microgravity, like on the ISS, is harmful to us, even with exercise. In my opinion this evidence is enough: prolonged microgravity is bad.
So 1.0 G good, 0 G bad, based on substantial long term experience. My point was that we need that same “substantial long term experience” with 0.17 G (Moon) and 0.38 G (Mars), and we don’t have it. Fifty-plus years, and we have, really, nothing.
I do know about the Gemini experiment. It was a good thing, a first among so many remarkable Gemini program firsts, and I hope tether technology has a long and fruitful future. But the test wasn’t nearly long enough and with enough people to answer the gravity question.
Advocates of all kinds of rotating habitats want to find out a minimum amount of gravity for good health, affecting the required size and spin rate, also taking Coriolis Effect into account. I’m in favor of this, but like many, I don’t want to give up on planetary surfaces just yet. I have great hopes for the Moon.
I appreciate your speculations for the Moon, two months down, one month up, and so on. I speculate too, but my hopes and speculations are not the same as evidence.
If I were emperor, my method of finding this out would be to just put a crew on the Moon for a year. After all, Scott Kelly and others have stayed a year in orbit in microgravity, so the Moon couldn’t be worse than that, perhaps much better.
The “minimum” gravity is 1G and a couple thousand feet of tether is the way to do it. Or spinning a miles-in-diameter artificial hollow moon.
Your “advocates of all kind” are trying to figure out something cheaper, easier, whatever, and I don’t think that is going to happen.
People living for extended periods in less than Earth gravity is not a good idea. They will debilitate and suffer permanent bone loss and other effects. The space colony movement came into existence because Mars does not make a good second home for humankind.
A rocket to take a worthwhile payload there, a lander that can land a worthwhile payload on the lunar surface, and resources to exploit like ice and solar energy on those peaks. We have all of this in some form. What is left is the reason to do it.
The reason is to begin humans expanding into the solar system. Not Mars. Space colonies built with lunar materials. This logical progression begins with a permanent cislunar presence off-world and continues with exploiting lunar resources to build a space solar power infrastructure. The space solar power revenues, essentially powering the entire planet, is then used to finance construction of Bernal spheres. All of this was studied in the 1970’s and now seems to have been forgotten in favor of retirement condos on Mars.
Water would meet two critical requirements in cislunar space: radiation shielding and propellant stock. It is of course also required for humans to drink and grow plants. It would also not be necessary to process water into cryogenic hydrogen and oxygen for a nuclear pulse propulsion system. Water by itself would work just fine and for travel to an icy body like Ceres or other destinations the radiation shield could be drained and used for reaction mass for deceleration into orbit. The crew would suffer some dosing in the time it took to reacquire shielding with ISRU. This would work on almost of the nearly 20 icy moons of the gas and ice giants with possible oceans. The exception would be Jupiter where only Callisto is outside the lethal radiation belts. But even Europa and Ganymede (the largest moon in the solar system) would be destinations as long as the spaceship had sufficient propellant to keep the radiation shields full and did not drain them. The massive shielding required to protect against cosmic radiation would provide protection from Jupiter radiation. These oceans may host complex life. Nobody denies this possibility. The Moon in the only place to acquire shielding, assemble, test, and launch nuclear missions.
The Moon is thus the enabler for the underwater exploration of alien oceans with submarines.
So not just geology.
Lots of Moon vs. Mars discussion on NASAWatch and one thread I posted “Moon is really close, and has water (ice)! What are we waiting for?”
Someone replied, “Moon has water? ice? 100% proof? You might want to check the data showing ppm ranges as the only hard physical evidence.” Someone else replied, “A robotic lunar polar lander with a rover might be needed to get more reliable data.”
Recent discussion by others about the Moon besides Dennis and Paul is some progress but a Mars mission is ***always*** attached to lunar mission concepts. I think right then it will bankrupt any lunar planning. My 2 cents.
Someone replied, “Moon has water? ice? 100% proof? You might want to check the data showing ppm ranges as the only hard physical evidence.”
It requires a real head of bone to believe that no water ice exists on the Moon in the face of direct evidence for 5-10 wt.% water vapor AND water ice particles in the ejecta of the LCROSS impact plume.
Someone else replied, “A robotic lunar polar lander with a rover might be needed to get more reliable data.”
Absolutely correct and if you read our proposed lunar architecture, you will see that we begin with a lander/rover mission to BOTH poles as the first steps in a return to the Moon.